"The light curve of the comet exhibited a slowdown event characterised by a constant brightness with no indication of a brightness increase tendency," he said.

The comet was discovered in 2012, and it had been hoped it would pass close enough to the sun to shine brightly in the sky from Earth. Nasa's Tony Phillips said at the time that:"If the comet survives the encounter, it could emerge glowing as brightly as the moon, visible near the sun in the blue daylight sky. The comet's dusty tail stretching into the night would create a worldwide sensation".

Ferrin's conclusions might start to dim those hopes along with the apparent brightness of the comet itself. But there is still help. As Space.com reports, the life and path of any comet it difficult to predict and ISON appears to be trickier than most. It is still possible that the comet may shine brightly once it completes its trip around the sun towards the end of November.